Single-wall carbon nanotubes (SWNT), commonly known as “buckytubes,” have been the subject of intense research since their discovery due to their unique properties, including high strength, stiffness, and thermal and electrical conductivity. Single-wall carbon nanotubes are fullerenes consisting essentially of sp2-hybridized carbon atoms typically arranged in hexagons and pentagons. For background information on single-wall carbon nanotubes see B. I. Yakobson and R. E. Smalley, American Scientist, Vol. 85, July-August, 1997, pp. 324-337. Multi-wall carbon nanotubes are nested single-wall carbon cylinders and possess some properties similar to single-wall carbon nanotubes. Multi-wall carbon nanotubes (MWNT) have been shown to be moderately effective in enhancing the electrical conductivity of composites that comprise MWNT in a polymer matrix. (see, for example S. A. Curran et al, Advanced Materials, Vol 10, p. 1091 (1998); J. N. Coleman et al., Physical Review B, Vol 58 p. R7492 (1998); Grimes et al., Chemical Physics Letters, Vol. 319, p. 460 (2000);and P. Foumet et al., Journal of Applied Physics, Vol. 90, p. 969 (2001)). However, since single-wall carbon nanotubes have fewer defects than multi-wall carbon nanotubes, the single-wall carbon nanotubes are generally stronger and more conductive, and are therefore expected to provide both mechanical enhancement and electrical conductivities in polymer composites. A small amount of work has been done in this area with methacrylate polymer matrices providing some useful results, but these results show relatively low electrical conductivities (Grimes et al., Chemical Physics Letters, Vol. 319, p. 460 (2000); R Haggenmueller et al., Chemical Physics Letters, Vol. 330, p. 219 (2000); J-M. Benoit et al., Synthetic Metals, Vol. 121, p. 1215 (2001)).
In polymers, single-wall carbon nanotubes have substantial potential for enhancing the polymers' strength, toughness, electrical conductivity and thermal conductivity. However, achieving the full potential of the properties of single-wall carbon nanotubes in polymers has been hampered by the difficulty of dispersing the nanotubes. A method for producing compositions comprising well-dispersed single-wall carbon nanotubes in polymeric materials is sought in order to achieve greater electrical and thermal conductivity in polymer composites.